Malicious PDF — malware analysis report

Static analysis result for SHA-256 bcb712810625b8ea…

MALICIOUS

PDF

106.0 KB Created: 2021-07-08 05:42:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: bb24ca7d7f06b6b03d3a2b9e28c6c46c SHA-1: 3fb23f94f06ac11d0be2439f9deebf9697a6eeb0 SHA-256: bcb712810625b8ea1c63466fafe838998afab3996dfb556fa53b63d7e2bdd778
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded URLs, with several pointing to compromised CMS upload storage and disposable hosting, indicative of a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. The heuristics indicate the document is designed to host a collection of links, potentially to trick users into visiting malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9790

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://kamkmori.cz/ckfinder/userfiles/files/nusexosekubirixux.pdf
    • http://www.ochoadentalcare.com/tacgestorcontenidos_ochoa/documentos/file/
    • https://pabausa.org/wp-content/plugins/formcraft/file-upload/server/content/files/160d99afe0a6ce---65569181653.pdf
    • http://taxilitomerice.cz/ckfinder/userfiles/files/raroxosu.pdf
    • https://tigaintan.com/contents//files/82116984815.pdf
    • https://thewentworthco.com/wp-content/plugins/super-forms/uploads/php/files/i1v4cr2s5m7agnr9qr55lchcns/fapimejepefin.pdf
    • http://www.neslihanonur.com/wp-content/plugins/super-forms/uploads/php/files/013d66f23f3fc44f4b13d66314c1a8c3/kerupix.pdf
    • http://ytovietnam.net/ckfinder/userfiles/files/38248392784.pdf
    • http://tdfinalists.ca/clients/43449/File/luzibasetapaxov.pdf
    • https://thepetrichortouch.com/wp-content/plugins/super-forms/uploads/php/files/vhijff4cfr1g7r3cbn7cfqmav1/nugawuxiwipexekulosubuzi.pdf
    • https://kantankacreative.com/wp-content/plugins/super-forms/uploads/php/files/3f959b04ba8b43a67ca7b1e03d944fb4/tigakimemapanuromi.pdf
    • https://123natura.com/stockages/files/teneletekuko.pdf
    • https://kassa-evotor.ru/wp-content/plugins/super-forms/uploads/php/files/nqkoj65p6bhg9si70chp161aad/9053696382.pdf
    • https://drainscovers.com/wp-content/plugins/super-forms/uploads/php/files/fb689cf59edef5a849304774562133dc/gosuguxuzomolodepikax.pdf
    • http://www.gametimecatering.com/wp-content/plugins/formcraft/file-upload/server/content/files/160780dba2799b---35793386736.pdf
    • https://brokenspoke.com/wp-content/plugins/super-forms/uploads/php/files/5592211cf78a51f0c1d67c20a5571554/34789348439.pdf
    • http://wsm.hk/images/files/21300948335.pdf
    • http://sofia-es.tokyo/yamituki-n/uploads/files/naguvivuzevavufasetaxoba.pdf
    • https://aulacvn.com/upload/fck/file/44382409466.pdf
    • https://levin-dent.ru/wp-content/plugins/super-forms/uploads/php/files/30dcfbeca2b964e473e2bc2d04df2dd9/90293987744.pdf
    • http://anandamsanyal.com/userfiles/file/wanivanif.pdf
    • http://aweibel.com/Photo/file/putigoboji.pdf
    • http://www.medical-psychology.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160869c439e6ec---gisesomusotogedenivopus.pdf
    • https://ferest.ro/imagini_ws/lotegovafiwizunirad.pdf
    • https://oneremote.ru/wp-content/plugins/super-forms/uploads/php/files/0f613452bc1b4e5d4595077dd6996c1a/kabugo.pdf
    • https://celovechurch.org/wp-content/plugins/super-forms/uploads/php/files/3295dcf2940f5a32009354b3167bf32b/26433858905.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=isley+brothers+greatest+hits+zip
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00013bf8.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13BF8 16792 bytes
font_01_sfnt_off0001540a.bin
3b288ececff12a82ff77fedf1938fa58891df1d90e4b903eb88fca216673b115
pdf-font-stream PDF embedded font (sfnt) at offset 0x1540A 17108 bytes
font_02_sfnt_off00018056.bin
88c8c745ee55a78a249517779d0aa1cdf39a0358a81545b8f7e0c6a8370285cd
pdf-font-stream PDF embedded font (sfnt) at offset 0x18056 10692 bytes